1. Field of the Invention
The present invention relates to biopsy devices, and, more particularly, to a handheld biopsy device having integrated vacuum assist to aid in tissue sample acquisition.
2. Description of the Related Art
A biopsy device has a sample retrieval mechanism configured to sever and remove a tissue sample from a patient. The sample retrieval mechanism may be in the form of a biopsy probe assembly that is configured with a biopsy needle having a sample retrieval opening. Some practitioners that perform biopsy procedures prefer a self-contained handheld biopsy device over that of a large console system. There are essentially two types of self-contained handheld biopsy devices: the partially disposable biopsy device and the fully disposable biopsy device.
A typical partially disposable biopsy device has a reusable handheld driver to which a disposable probe is releasably attached. The reusable handheld driver is typically battery powered, and includes electrical motor drives and an on-board vacuum pump to aid in sample acquisition and/or retrieval. Often, such biopsy devices are configured for single insertion multiple sample (SIMS) procedures. The disposable probe is used on a single patient, and then discarded, while the handheld driver is retained for reuse.
A typical fully disposable biopsy device has one or more mechanical drives, such as spring/latch arrangements, which permit the biopsy device to be manually cocked and fired for tissue sample acquisition. Such simple biopsy devices often are configured to acquire a single sample per insertion. Also, many of the fully disposable biopsy devices do not have vacuum to assist in sample acquisition. While some attempts have been made to include a vacuum assist feature in a fully disposable biopsy device, the vacuum produced typically is not sufficient to approach the performance of that of a partially disposable biopsy device as described above. Also, in a typical fully disposable biopsy device having vacuum assist, such vacuum is generated simultaneously with movement of the cutting cannula to sever the tissue sample, and thus the vacuum may be of limited value in acquiring the tissue sample.
What is needed in the art is a biopsy device that may be fully disposable, and which may generate a reserve of vacuum prior to a retraction of the cutting cannula to expose the sample retrieval opening of the biopsy needle, thus facilitating efficient vacuum application to aid in sample acquisition, and which is configured to be easy to use.